A digital signal processor (DSP) is a specialized microprocessor designed specifically for digital signal processing. Some digital signal processing tasks require the calculation of discrete Fourier Transforms. A particularly fast way to perform discrete Fourier Transforms is known as the Fast Fourier Transform (FFT) method. To perform the FFT quickly and efficiently, the DSP will likely include multiply-accumulate functionality. A program written using the instruction set of the DSP will enable the FFT calculation to be performed using the specialized hardware of the DSP.
The design of the DSP and its instruction set involves a balance between various competing goals, including reduction of the code size of programs, limits on the physical size of the DSP, and the speed of certain calculations.
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